/*******************************************************************************
 * Copyright 2010 Ray Ling
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *   http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 ******************************************************************************/
package org.ring.rinject.collection;

import java.util.HashMap;
import java.util.Map;

import org.ring.rinject.exception.AlreadyMappedException;

public class Mapper<B,C> {
	protected final Map<B, Wrapper<C>> mapper;

	public Mapper() {
		mapper = new HashMap<B, Wrapper<C>>();
	}
	
	public Mapper<B, C> set(B base, C concrete)
		throws AlreadyMappedException{
		return set(base, concrete);
	}

	public Mapper<B, C> set(B base, C concrete, boolean overwrite) 
		throws AlreadyMappedException{
		if (overwrite || (!mapper.containsKey(base))) {
			Wrapper<C> wrapper = new Wrapper<C>(concrete);
			mapper.put(base, wrapper);
		}else{
			throw new AlreadyMappedException("Base["+base+"] is already mapped!", concrete ,mapper.get(base));
		}
		
		return this;
	}
	
	public Wrapper<C> concrete(B base){
		return mapper.get(base);
	}
}
